"How can I run the the graphical interface."
You can set up the GUI monitor configuration on an installed SuSE system by using the command line program sax2. Log in as root and open a terminal. Then type in the command sax2.
If your monitor is screwed up so much that you cannot use the GUI even to log in as root then boot to the login screen and hit the three finger command <cntl> <alt> <F3> which will give you a command line login prompt on virtual console 3. You have six virtual consoles available, F1 through F6, available if you need them. <cntl> <alt> <F7> will take you back to the GUI login screen after you straighten out your monitor with sax2.
Be prepared. Create a LifeBoat CD.